[S3 guidelines on diagnostics and therapy of bipolar disorders: development process and essential recommendations]. / S3-Leitlinie zur Diagnostik und Therapie bipolarer Störungen: Entwicklungsprozess und wesentliche Empfehlungen.

Bipolar disorders are severe psychiatric disorders with extensive individual and health economic consequences. Starting in 2007 the first German evidence and consensus based guideline for diagnostics and treatment of bipolar disorders was developed which holds the potential of increasing confidence of therapists, patients and relatives in the decision-making process and improving healthcare service experiences of patients and relatives. Apart from recommendations for diagnostics and treatment the guidelines provide those for trialogue action, knowledge transfer and self-help and for strategies for healthcare provision of this complex disorder. In the present article the methodology and essential recommendations are outlined and complemented in specific topics by corresponding articles in this special issue. Due to restrictions of the length of this presentation there is the need to refer to the comprehensive version of the guidelines at several points also regarding a detailed discussion of the limitations.

Carcinogen and anticancer drug transport by Mrp2 in vivo: studies using Mrp2 (Abcc2) knockout mice.

The ATP-binding-cassette (ABC) transporter multidrug resistance protein (MRP) 2 (ABCC2) forms a natural barrier and efflux system for various (conjugates of) drugs, other xenotoxins, and endogenous compounds. To obtain insight in the pharmacological and physiological functions of Mrp2, we generated Mrp2 knockout mice, which were viable and fertile but suffered from mild hyperbilirubinemia due to impaired excretion of bilirubin monoglucuronides into bile. The mice also had an 80-fold decreased biliary glutathione excretion and a 63% reduced bile flow. Levels of Mrp3 (Abcc3) in liver and Mrp4 (Abcc4) in kidney of Mrp2-/- mice were approximately 2-fold increased. After oral administration of the food-derived carcinogens [(14)C]PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine) and [14C]IQ (2-amino-3-methylimidazo[4,5-f]quinoline) plasma values were 1.9- and 1.7-fold higher in Mrp2-/- mice versus wild-type mice, respectively, demonstrating the role of Mrp2 in restricting exposure to these compounds. At a high dose of 50 mg/kg of the drug [3H]methotrexate, the plasma area under the curve for i.v. administration was 1.8-fold higher in Mrp2-/- mice (1345+/-207 versus 734+/-81 min.microg/ml). No clear plasma concentration difference arose at low dose (1 mg/kg). Subsequently, Mdr1a/b/Mrp2 knockout mice were generated. Their biliary excretion of doxorubicin after i.v. administration (5 mg/kg) was 54-fold decreased (0.32+/-0.13 versus 17.30+/-6.59 nmol/g liver in wild type), and a role for both Mdr1a/b and Mrp2 in this process was revealed. Our results demonstrate that the Mrp2-/- mouse provides a valuable tool for studies of the impact of Mrp2 on behavior of drugs and other toxins, especially when combined with other ABC transporter knockout mice.

High mutation rate in dopa-responsive dystonia: detection with comprehensive GCHI screening.

Mutations in GTP cyclohydrolase I (GCHI) are found in 50 to 60% of cases with dopa-responsive dystonia (DRD). Heterozygous GCHI exon deletions, undetectable by sequencing, have recently been described in three DRD families. We tested 23 individuals with DRD for the different mutation types by conventional and quantitative PCR analyses and found mutations, including two large exon deletions, in 87%. The authors attribute this high mutation rate to rigorous inclusion criteria and comprehensive mutational analysis.

Phenylalanine loading as a diagnostic test for DRD: interpreting the utility of the test.

Phenylalanine loading has been proposed as a diagnostic test for autosomal dominant DRD (dopa-responsive dystonia), and recently, a phenylalanine/tyrosine (phe/tyr) ratio of 7.5 after 4 h was reported as diagnostic of DRD. To test the utility of this test in another sample with DRD, we administered an oral challenge of phenylalanine (100 mg/kg) to 11 individuals with DRD and one non-manifesting gene carrier. Only 6/12 had a 4 h phe/tyr ratio of greater than 7.5, suggesting that additional parameters must be set to avoid missing the diagnosis of DRD, including the need for the plasma phenylalanine to reach a minimum level 600 in order for the test to be valid. We propose that in cases where this minimum plasma phenylalanine level is not reached, plasma tetrahydrobiopterin should be measured or alternatively other symptomatic family members should be screened.

Exon deletions in the GCHI gene in two of four Turkish families with dopa-responsive dystonia.

Most cases of dopa-responsive dystonia (DRD) are thought to be caused by mutations in the GCHI gene; however, by sequencing, mutations are found in only 40% to 60%. Recently, a single report identified, via Southern blot analysis, a large genomic GCHI deletion in a "mutation-negative" case. This report describes four families with DRD, two of which carry large deletions, thus confirming that deletions are an important subtype of GCHI mutations. These deletions were detected by quantitative duplex PCR that is amenable to DNA diagnostics.

Accumulation of rab4GTP in the cytoplasm and association with the peptidyl-prolyl isomerase pin1 during mitosis.

Transport through the endocytic pathway is inhibited during mitosis. The mechanism responsible for this inhibition is not understood. Rab4 might be one of the proteins involved as it regulates transport through early endosomes, is phosphorylated by p34(cdc2) kinase, and is translocated from early endosomes to the cytoplasm during mitosis. We investigated the perturbation of the rab4 GTPase cycle during mitosis. Newly synthesized rab4 was less efficiently targeted to membranes during mitosis. By subcellular fractionation of mitotic cells, we found a large increase of cytosolic rab4 in the active GTP-form, an increase not associated with the cytosolic rabGDP chaperone GDI. Instead, phosphorylated rab4 is in a complex with the peptidyl-prolyl isomerase Pin1 during mitosis, but not during interphase. Our results show that less efficient recruitment of rab4 to membranes and a bypass of the normal GDI-mediated retrieval of rab4GDP from early endosomes reduce the amount of rab4GTP on membranes during mitosis. We propose that phosphorylation of rab4 inhibits both the recruitment of rab4 effector proteins to early endosomes and the docking of rab4-containing transport vesicles. This mechanism might contribute to the inhibition of endocytic membrane transport during mitosis.

Rabaptin4, a novel effector of the small GTPase rab4a, is recruited to perinuclear recycling vesicles.

The small GTPase rab4a is associated with early endocytic compartments and regulates receptor recycling from early endosomes. To understand how rab4a mediates its function, we searched for proteins which associate with this GTPase and regulate its activity in endocytic transport. Here we identified rabaptin4, a novel effector molecule of rab4a. Rabaptin4 is homologous with rabaptin5 and contains a C-terminal deletion with respect to rabaptin5. Rabaptin4 preferentially interacts with rab4a-GTP and to a lesser extent with rab5aGTP. We identified a rab4a-binding domain in the N-terminal region of rabaptin4, and two binding sites for rab5, including a novel N-terminal rab5a-binding site. Rabaptin4 is a cytosolic protein that inhibits the intrinsic GTP hydrolysis rate of rab4a and is recruited by rab4a-GTP to recycling endosomes enriched in cellubrevin and internalized indocarbocyanine-3 (Cy3)-labelled transferrin. We propose that rabaptin4 assists in the docking of transport vesicles en route from early endosomes to recycling endosomes.

Regulation of membrane transport through the endocytic pathway by rabGTPases.

Small GTP binding proteins of the rab family are associated with the cytoplasmic surface of compartments of the central vacuolar system. Several of them, including rab5, rab4 and rab11, are localized to early endocytic organelles where they regulate distinct events in the transferrin receptor pathway. Whereas rab5 is controlling transport to early endosomes, rab4 and rab11 are involved in the regulation of recycling back to the plasma membrane. How GTP-hydrolysis of rab bound GTP is related to the role of these proteins in endocytosis is not yet known, but quick progress is being made towards this goal through the identification of proteins regulating the activity of these rab proteins.

A novel epitope tag for the detection of rabGTPases.

Rab GTPases are localized on the cytoplasmic surface of most intracellular organelles where they play a role in the regulation of vesicular transport. As it has been difficult to detect endogenous rab proteins by morphological methods, their localizations were often inferred from transfection experiments using epitope-tagged constructs. Because most of the available epitope tags are only recognitzed by mouse monoclonal antibodies they are often not suitable for double or triple label immunocytochemistry. To overcome this problem, we generated antibodies against a novel 10 amino acid X31 influenza hemagglutin epitope (NH). We here characterized these antibodies and document their utility for detecting early endosomal rab proteins N-terminally tagged with the NH decapeptide in morphological and biochemical assays.

Effects on the offspring of chronic low exposure carbon monoxide during mice pregnancy.

This research is primarily concerned with the effects of chronic low doses of carbon monoxide on fetal development. Carbon monoxide was administered daily by inhalation to female Swiss Webster mice from the beginning of gestation until term. Daily weights were recorded and carbon monoxide blood levels determined every 4 days. The number of offspring in each litter was recorded. At weaning, two males and two females from each litter were randomly picked for maze running studies. When the mice were 6 weeks old, they were tested daily, ten trials per day, in the maze until learning had occurred. The number of days required to learn the maze and the number of incorrect trials were recorded. While there was no significant increase in the number of days needed to learn the maze, there was a significant increase in the number of errors made by the experimental group during this time. This indicated that an increased effort was needed to learn the maze.